Official Luthiers Forum!

I have the Delta 31-255 thickness sander (18-36"). A few weeks ago I had the paper pull out of the clip on one side. This had not happened in the previous year of using it and now it has happened 3 times in the last 2 hours of use.

The problem is actually kind of serious, for one you ruin the paper, but more importantly it can bunch up and damage the wood - I took a good chunk out of a top this morning.

Has anyone seen and fixed this problem?

_________________
David White, Toronto

"All my favourite singers can't sing."

all I know is the delta's didnt get very good reviews at many of the wood working sights.........................Jody

It can happen with any of them.

Maybe the hook and loop guys will chime in.

I've not heard of hook and loop coming off, but if it were to get started, I'm sure it'd rip undone as well.

On my General it has two clips. The pulling side has a tension spring to keep the paper taught. The leading side has a static clip. As the paper expands or slips out of the lead clip, the spring side can compensate for a little bit, before what you mentioned happens.

Good luck finding your problem. Never ruined a set yet and I've had it happen a dozen times. You have to be ready for that eventuality and unwind the clearance fast. Shutting it down is only an option after the fact. Quickest thing is to add clearance and pronto.

Side Note: The sounds a machine makes while running, will clue you into impending failure. Time to stop and take a look. Oh, and I'm probably not the only person that adds a strip of reinforced strapping tape to the lead edge to assist the lead clip. You just have to compensate by not feeding wood into that area to be sanded.

_________________
http://www.dickeyguitars.com

A bit of a hijack here

Though very conveniont when loading paper it would seem to me that hook and loop would ad a bit of cushion between the drum and the paper and could make for inconsistent thickness. I could be wrong here because I have never used one with hook and loop but just seems intuitive. If I am wrong here I gather then the amount of padding is consistant across the entire dum enough to be accurate with.

I have the 31-250, older model. No paper problems till a few months ago I loaded some 36 grit paper, it came undone. BANG! Whappedy whappedy whappedy! I changed to another (36 grit) roll. Same thing. Waited a few months, and 2 weeks ago successfully used it. Could be operator error, but I probably didn't take the time to "split the difference" regarding the amount left on the end for the clips to grab.

When I get a new shop, I'll likely grab the first 25" dual drum Grizzly I see next. (couple times a year about $500-$700 locally)

One of the messages constantly broadcast on woodworkers' sites is that you should not expect your thickness sander to function as a planer. I cannot imagine putting 36 grit sandpaper into my Delta thickness sander...the coarsest I go is about 120 grit.

The problem is that you're trying to remove too much stock in one pass and the clips on the drum cannot hold the paper in place. Forget contact cement and such. Just slow down!

I use a 15" Jet planer with a Shelix cutter head to mill stock to near-final thickness. If it's a top or back that will be edge glued, I leave 1/16" extra thickness. After gluing, I remove any excess glue using a scraper.

I then make multiple passes (twenty might be about right) through the drum sander, making sure the glue doesn't clog the paper. I run the feed fast (the wood should not feel warm when it exits the drum) while removing very little material on each pass. Between height adjustments, each side of the piece goes through twice to assure equal thickness. When the material is near final thickness, I slow the feed rate down while raising the table height only very slightly. At this point, I'm usually taking four passes through the sander on each side between height adjustments.

A rubber sandpaper cleaning stick will help make your sandpaper strips last much longer, by the way.